The statements in this section merely provide background information related to the present disclosure and may not constitute prior art
Ceramic foam materials are well known for their excellent mechanical properties and stability at high temperature and have been widely used as high temperature structural materials in many fields, including in the aeronautic fields. Due to manufacturing constraints and/or varying three dimensional surfaces, it is difficult to manufacture large ceramic foam structures from a single piece of ceramic material. Therefore, large ceramic foam structures are typically constructed from a multitude of ceramic blocks or pieces that are bonded to one another.
Bonding two or more ceramic blocks together to form a single structure presents challenges. Traditional joining or bonding technologies like mechanical connection, diffusion bonding and brazing are used for ceramic-to-ceramic connections. However, each of these known techniques has drawbacks.
Another method of bonding two or more ceramic foam pieces together is to use a bonding material that functions as a permanent adhesive. Under current practices, when a bonding material is used, each ceramic face that is bound to an adjacent ceramic face is sealed in order to create a robust bonding surface. However, sealing the ceramic face bonding surfaces inhibits the flow of air through ceramic foam materials and, therefore, inhibits heating or cooling of the ceramic foam structures. In addition the bonding material can be a continuous material and thereby act as a seal between adjacent ceramic pieces.
Although there has been limited success with known methods of bonding porous ceramic components, challenges still exist. Accordingly, there is a need for improved bonding compositions and bonding methods that are capable of bonding to ceramic foam articles without severely impacting the porosity and air flow characteristics of the material.